Merge branch 'list-deselect-event'

Consistently send DESELECTED events from virtual wxListCtrl.

See https://github.com/wxWidgets/wxWidgets/pull/1857

interface/wx/listctrl.h

@@ -1442,7 +1442,7 @@ protected:
         control itself when this event is generated, see @ref
         overview_events_with_mouse_capture "event handling overview".
     @event{EVT_LIST_ITEM_DESELECTED(id, func)}
-        The item has been deselected.
+        The item has been deselected. GetIndex() may be -1 with virtual lists.
     @event{EVT_LIST_ITEM_ACTIVATED(id, func)}
         The item has been activated (ENTER or double click).
     @event{EVT_LIST_ITEM_FOCUSED(id, func)}